Pattern of gonad maturation and the question of semelparity in the paedomorphic goby Aphia minuta

At variance with previous reports, the paedomorphic goby Aphia minuta does not show semelparity, but abbreviate iteroparity like other small Mediterra nean gobiid species. In spring, the mature ovary contains several batches o f eggs at different stages of vitellogenesis. This indicates that the breed ing season of A. minuta is quite long and that spawning takes place at leas t twice during its short lifespan, involving in each ovulatory wave differe nt batches of oocytes which undergo vitellogenesis at different times. Thes e observations agree with the testicular cycle data. In males, which in spr ing exhibit active spermiation coinciding with deposition of the first batc h of oocytes, spermatogonial mitosis also resumes, eventually resulting in the production of new sperm in summer. (C) 2001 The Fisheries Society of th e British Isles.